I'm currently looking to pick up a bow mount trolling motor for my boat. It's a 1960 Lowe Roughneck. I've got the main 70 hp motor and a 25 hp backup. I figure you can never be too safe since I fish mainly rivers with a lot of current. I'm just wondering how much thrust you all think I would need? I'm looking for something that can get me to the bank or maybe move be upstream should both other motors fail. Thanks for your help.